September 2026 Calendar: Five Tuesdays, One Monza Sunday
September 2026 opened on a Tuesday and closed on a Wednesday, a tidy 30 days with five Tuesdays and five Wednesdays. On Sunday, September 6, Monza produced the drive of the year. Kimi Antonelli charged from deep in the field to win his home Italian Grand Prix. The month held 22 business days and eight weekend days, and autumn arrived on time, with the equinox on Wednesday, September 23. The blank grid below is the whole point. Here is what filled it.
The shape of the month
The 30 days ran across weeks 36 to 40. Last quarter fell around Friday, September 4, the new moon around Friday, September 11, first quarter around Friday, September 18. Every phase took a Friday this month, which made the lunar calendar unusually easy to memorize.
The full moon, this year's Harvest Moon, rose around Saturday, September 26. That was three nights after the equinox on Wednesday, September 23. Twenty-two business days put September between August's 21 and December's 23, and eight weekend days kept the pace honest.
The Atlantic, meanwhile, set a satellite-era record: no hurricane formed all month. The season's first would not arrive until October. The quiet run made the storm maps almost boring, and nobody minded.
From Monza to New York to Nagoya
Antonelli's Monza win, for Mercedes, was the first home victory for an Italian driver since 1966. Starting 19th is usually a good view of the midfield. On Sunday, September 6, it was a launch pad, and the crowd kept the noise going long after the flag.
The US Open finished the next weekend. Elena Rybakina came from a set down to beat two-time defending champion Aryna Sabalenka on September 12. Alexander Zverev then took his first US Open title over Ben Shelton in four sets on September 13.
On Saturday, September 19, Emperor Naruhito opened the Asian Games in Nagoya, the third Japanese city to host. The games ran through October 4, which made late September and early October one long sports corridor.
The Emmys filled September 14. The comedy-horror hit Widow's Bay set a comedy-series record with 14 awards, while The Pitt defended best drama.
The rest of the record
Norway began the month with a new king. Crown Prince Haakon took his oath as Haakon VIII before the Storting on September 1. Ingrid Alexandra became Crown Princess.
OpenAI released GPT-6 Astra on September 3, its most capable model to date. Its context window holds roughly one million tokens. Sweden's general election on September 13 ended 176 seats to 173 and toppled Prime Minister Ulf Kristersson. On September 29, Morocco's king appointed Fatima Ezzahra El Mansouri as the country's first female prime minister.
The month also grieved. A fire consumed the passenger ferry MV June Aster off Coron, Palawan, on September 9. At least 76 people died, among the Philippines' deadliest maritime disasters in years.
October 2026 opens on a Thursday and keeps five Saturdays. The fourth quarter starts politely, then fills its squares fast.